PHASE II REPORT - Caltrans

Table 5.1: Plackett-Burman Design for the Six Condition Variables
Observation X1 X2 X3 X4 X5 X6
1 +1 +1 +1 -1 +1 -1
2 -1 +1 +1 +1 -1 +1
3 -1 -1 +1 +1 +1 -1
4 +1 -1 -1 +1 +1 +1
5 -1 +1 -1 -1 +1 +1
6 +1 -1 +1 -1 -1 +1
7 +1 +1 -1 +1 -1 -1
8 -1 -1 -1 -1 -1 -1
Ruggedness tests results for the AMT are contained in Appendix C.
5.3.2 CAT Test
For this test, the condition variables are:
• X1 Cure Time
• X2 Cure Temperature
• X3 Humidity of Cure
• X4 Test Time (Abrasion Time)
• X5 Test Temperature
• X6 Duration of Test
Since compaction was evaluated and considered not necessary, this is not a variable for which
its value is to be controlled as is the case for the other condition variables whose effects are
being studied. The experiments will be the same and the same as the Plackett-Burman
experiment given for the AMT, with three replications of selected combinations. There will not
be an X7 variable, but the other six variables will be as given.
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